Reverse flow hydraulic pump-turbine systems



Nov. 2, 1965 A. wElBl-:L

REVERSE FLOW HYDRAULIC PUMP-TURBINE SYSTEMS Filed Jan. 22. 1964 Nov. Z, 1965 A. wElBr-:L 3,214,915

REVERSE FLOW HYDRAULIC PUMP-TURBINE SYSTEMS Filed Jan. 22, 1964 3 Sheets-Sheet 2 Nov. 2, 1965 A. wElBEL 3,214,915

REVERSE FLOW HYDRAULIC PUMP-TURBINE SYSTEMS Filed Jan. 22, 1964 3 Sheets-Sheet 3 TURBlNE REVERSIBLE (0R REVERSIBLE PUMP-TURB|NE PuMP-TURBINE) H GENERATOR/MOTOR FREEWHEEL DEVICE FIGA United States Patent Gtiice 3,214,915 Patented Nov. 2, 1965 3,214,915 REVERSE FLOW HYDRAULIC PUMP-TURBWE SYSTEMS Andr Weibel, Winterthur, Switzerland, assignor to The English Electric Company Limited, London, England, a British company Filed Jan. 22, 1964, Ser. No. 339,468 Claims priority, application Switzerland, Jan. 29, 1963,

1,033/ 63 7 Claims. (Cl. 60-55) This invention relates to a pumped storage system in which two reservoirs or the like are provided at different levels.

Embodiments of the invention will be described by way of example with reference to the accompanying drawings, of which:

FIG. 1 shows diagrammatically a pumped storage system in accordance with the invention,

FIG. 2 is a detail of part of FIG. l, drawn in section, and with parts broken away,

FIG. 3 is a View in the direction of the arrow Ill in FIG. 2, and

FIG. 4 shows a modification of part of the pumped storage system.

Referring to the drawings, a reversible pump-turbine 11 is connected through a shaft 12 to the rotor of generator/motor 13. The reversible pump-turbine has a blade rotor 14 (FIGS. 2 and 3) mounted in a casing 15, water flowing inward adjacent the periphery 16 of the bladed rotor and axially out of the eye 17 during turbine operation, when power is transmitted to the machine 13 causing it to act as a generator, and in the reverse direction during pump operation when the machine 13 acts as a -motor and drives the bladed rotor. Rotation of the bladed rotor 14 during pump operation is in the reverse sense to rotation during turbine operation. The reversible pump-turbine 11 is provided with a spiral casing 18 surrounding the periphery 16 of the bladed rotor, and there is provided a ring of adjustable guide vanes 19 immediately surrounding the periphery 16 of the bladed rotor, the inclination of the guide vanes being adjusted in known fashion for pump and turbine operation through a control ring 20 by means of a mechanism dagrammatically shown at 21.

Also connected to the rotor of the generator/motor 13 through a shaft 22 in a turbine 23, of similar 4construction to the reversible pump-turbine 11. The turbine 23 thus has a runner 34, a casing 35, a spiral casing 38, surrounding the periphery 36 of the runner, and adjustable guide vanes 39 operated through a control ring 40' by a mechanism 41', the parts serving the same functions as in the reversible pump-turbine 11. The turbine 23 is preferably non-reversible and a suitable free-wheel device 24 is therefore provided between the turbine and the generator/motor 13, allowing a drive from the turbine 23 to the generator/motor 13, but not vice versa. Reduction gearing may also be provided if desired between the reversible pump-turbine 11 and the generator/motor 13, and/or between the generator/motor 13 and the turbine 23. lf desired instead of a non-reversible turbine 23 there may be a reversible pump-turbine connected to shaft 22, in which case the free-wheel device 24 must be omitted. The pumped storage system has two storage reservoirs 40, 41 located at different heights above the level of the turbine/ generator unit (i.e., the unit comprising a reversible pump-turbine 11, a generator/motor 13, and a turbine, or reversible pump-turbine 23) or units; for example, the upper reservoir 40 may be 2,500 ft. above the level of the units, and the lower reservoir 41 may be 1,250 ft. above the level of the unit or units.

Leading from the upper reservoir 40 to the reversible pump-turbine 11 is a pipe-line 42 off which is branched a pipe-line 43 leading to the spiral casing 18 and provided with a valve 44. There may also be a discharge line (not shown) branching from pipe-line 42.

A further pipe-line 45 is connected to the eye of the reversible pump-turbine 11 and divides into two pipelines 46, 47, of which pipe-line 46 includes a valve 48 and is connected to the lower reservoir 41, and pipe-line 47 includes .a valve 49 and is connected to the spiral casing 38 of turbine 23. A further pipe-line 50 containing a valve 51 interconnects pipe-line 46 and pipe-line 47 between valve 49 and turbine 23. A further pipe-line 52 is connected to the eye 37 of the turbine 23 and leads to waste or toa reservoir or the like 53.

There may be a second identical turbine/generator unit, or any convenient number of such units, connected to the two reservoirs 49, 41. The second turbine/ generator unit has a reversible pump-turbine 11 connected to a generator/motor 13', and is designated by the dashed reference numerals.

In operation as a turbine, each turbine/ generator unit may be lsupplied either from the higher reservoir 40 `or the lower reservoir 41. If it is supplied from the higher reservoir 40 the water flows through pipe-lines 42 and 43 to spiral casing 18, the valve 44 being open, to drive the reversible pump-turbine 11, which transmits power to the generator/motor 13. The adjustable guide vanes 19 are adjusted by control mechanism 21 to the position appropriate to turbine operation. The water flows away from the reversible pump-turbine 11 through pipe-line 45. By suitable adjustment of valves 4S and 49 the water may be caused to ow wholly through pipe-line 46 to the lower reservoir 41, or wholly through pipe-line 47 to turbine 23, or partly through pipe-line 46 and partly through pipe-line 47. Where part or the whole of the water Hows through pipe-line 47 to turbine 23, the latter constitutes the low-pressure part of the unit, the reversible pumpturbine 11 constituting the lhigh-pressure part, and the machines are designed accordingly. Thus the total available head may `be employed in two stages to drive the machine 13 as a generator. The water leaves the turbine 23 through pipe-'line 52 and flows to waste.

Where the turbine/generator unit is to be supplied from the lower reservoir 41, the water flows through pipe-lines 46 and 50 to the spiral casing 38 of turbine 23, and the generator/motor 13 is driven solely by turbine 23.

During this mode of operation the reversible pumpturbine 11 may be emptied of water by the introduction through a conduit 18 of `Compressed air, in known fashi-on, yso as to reduce losses due to its rotation. The water from turbine 23 flows through pipe-line 52 to waste.

During pumping operation, water is supplied from the lower reservoir 41 through pipe-lines 46 and 45 to the reversible pump-turbine 11 which is driven by the generator/motor 13 acting as a motor. The adjustable guide vanes 19 are adjusted by the control mechanism 21 to the position appropriate for operation as a pump, and the water is delivered to spiral casing 18 and from there through pipe-lines 43 and 42 to the higher reservoir 40. Valves 44 and 48 will be open during this operation.

The operation of the second turbine/ generator unit 11', 13', 23' is of course identical with that above described.

Where water is `supplied through the reversible pumpturbine 11 and the turbine 2'3 in series, the adjustable guide vanes 19, 39 will be adjusted so that the pressure drop through the two machines bears the desired relationship, for example, so that the 4overall etliciency has the optimum value.

Where the turbine 23 alone is supplied from the lower reservoir 41, the adjustable guide vanes 39 will be suitably adjusted; similarly during pumping operation the guide vanes 19 will be suitably adjusted. The adjustable guide vanes may be regulated lautomatically or manually.

In a modification of the arrangement described above, the turbine 23 is constructed as a reversible pump-turbine, in which ease a suitable reservoir 53 must be provided from which Water may be drawn through pipe-line 52. This water is delivered by the reversible pump-turbine 23, acting as a pump, either through pipe-line 47 to the eye 17 of reversible pump turbine 11, which in turn operates as a pump to deliver it through pipe-lines 43 and 42 to the upper reservoir 40 (the valves 44, 49 being open), or it may be delivered through pipe-lines 50 and 46 to the lower reservoir 41, valve 51 being open.

Instead of the reversible pump-turbine 11 and lowpressure turbine 23 being connected direct to the rotor of the generator/ motor 13, one or both may be connected through suitable gearing 25.

What I claim as my invention and desire to secure by Letters Patent is:

1. In or for a pumped storage system in which is provided a higher and a lower reservoir at different levels, a reversible pump-turbine having an eye and a periphery, a turbine having a periphery, a generator/motor, driving connections between said generator/mmol and said reversible pump-turbine and said turbine, first pipe means interconnecting the higher reservoir and the periphery of said reversible pump-turbine, second pipe means interconnecting the periphery of said turbine and said lower reservoir, third pipe means interconnecting the eye of said reversible pump-turbine and the periphery of said turbine, and fourth pipe means interconnecting the eye of said reversible pump-turbine and said lower reservoir, whereby water may ow alternatively, rst from the higher reservoir through the reversible pump-turbine to drive it and then to the lower reservoir, secondly, from the higher reservoir through the reversible pump-turbine and the turbine in series to drive them, thirdly from the lower reservoir to the turbine to drive it, and fourthly, from the lower reservoir to the reversible pump-tubine to be pumped up to the higher reservoir.

2. Apparatus as claimed in claim 1, wherein said turbine is non-reversible, and a free-wheel device is provided in the driving connection between the generator/ motor and the turbine, so that a drive can be transmitted from the turbine to the generator/motor but not vice versa.

3. Apparatus as claimed in claim 1, wherein said reversible pump-turbine and said turbine are connected direct to said generator/motor to rotate at the same speed as said generator/motor.

4. Apparatus as claimed in claim 1, wherein said reversible pump-turbine and said turbine are connected through gearing to said generator/motor to rotate at speeds different from that of said generator/motor.

5. In or for a pumped storage system in which is provided a highest, an intermediate and a lowest reservoir at different levels, a first reversible pump-turbine having an eye and a periphery, a second reversible pump-turbine having an eye and a periphery, a generator/motor, driving connections between said generator/motor and said first and second reversible pump-turbines, rst pipe means interconnecting the highest reservoir and the periphery of said first reversible pump-turbine, second pipe means interconnecting the periphery of said second reversible pump-turbine and the intermediate reservoir, third pipe means interconnecting the eye of said first reversible pump-turbine and the periphery of said second reversible pump-turbine, fourth pipe means interconnecting the eye of said first reversible pump-turbine and said intermediate reservoir, and fifth pipe means interconnecting the eye of said second reversible pump-turbine and the lowest reservoir, whereby water may ow alternatively, tirst from the highest reservoir through the rst reversible pumpturbine to drive it and then to the intermediate reservoir, secondly, from the highest reservoir through the first reversible pump-turbine and the second reversible pumpturbine in series to drive them and then to the lowest reservoir, thirdly, from the intermediate reservoir to the second reversible pump-turbine to drive it and then to the lowest reservoir, fourthly from the intermediate reservoir to the first reversible pump-turbine to be pumped up to the highest reservoir, fifthly, from the lowest reservoir through the second reversible pump-turbine and then through the first reversible pump-turbine to be pumped up to the highest reservoir, and siXthly, from the lowest reservoir through the second reversible pump-turbine to be pumped up to the intermediate reservoir.

6. Apparatus as claimed in claim 5, wherein said first and second reversible pump-turbines are connected direct to said generator/motor to rotate at the same speed as said generator/motor.

'7. Apparatus as claimed in claim 6, wherein said first and second reversible pump turbines are connected through gearing to said generator/motor to rotate at speeds different from that of said generator/motor.

References Cited by the Examiner UNITED STATES PATENTS 2,246,472 6/41 Sharp 60--55 X FOREIGN PATENTS 662,342 3/29 France. 862,498 3 61 Great Britain.

JULIUS E. WEST, Primary Examiner. 

1. IN OR FOR PUMPED STORAGE SYSTEM IN WHICH IS PROVIDED A HIGHER AND A LOWER RESERVOIR AT A DIFFERENT LEVELS, A REVERSIBLE PUMP-TURBINE HAVING AN EYE AND A PERIPHERY, A TURBINE HAVING A PERIPHERY, A GENERATOR/MOTOR, DRIVING CONNECTIONS BETWEEN SAID GENERATOR/MOTOR AND SAID REVISSIBLE PUMP-TURBINE AND SAID TURBINE, FIRST PIPE MEANS INTERCONNECTING THE HIGHER RESERVOIR AND THE PERIPHERY OF SAID REVERSIBLE PUMP-TURBINE, SECOND PIPE MEANS INTERCONNECTING THE PERIPHERY OF SAID TURBINE AND SAID LOWER RESERVOIR, THIRD PIPE MEANS INTERCONNECTING THE EYE OF SAID REVERSIBLE PUMP-TURBINE AND THE PERIPHERY OF SAID TURBINE, AND FOURTH PIPE MEANS INTERCONNECTING THE EYE OF SAID REVERSIBLE PUMP-TURBINE AND SAID LOWER RESERVOIR, WHEREBY WATER MAY FLOW ALTERNATIVELY, FIRST FROM THE HIGH RESERVOIR THROUGH THE REVERSIBLE PUMP-TURBINE TO DRIVE IT AND THEN TO THE LOWER RESERVOIR, SECONDLY, FROM THE HIGHER RESERVOIR THROUGH THE REVERSIBLE PUMP-TURBINE AND THE TURBINE IN SERIES TO DRIVE THEM, THIRDLY FROM THE LOWER RESERVOIR TO THE TURBINE TO DRIVE IT, AND FOURTHLY, FROM THE LOWER RESERVOIR TO THE REVERSIBLE PUMP-TURBINE TO BE PUMPED UP TO THE HIGHER RESERVOIR. 